Razor blade sharpener



July 27, 1937, EJA. JOHNSTON 2,088,111

RAZ R BLADE :SHARPENER Filed Dec. 30, 1935 2 1". Y I Inca/ 1502? Patented July 27, 1937 UNITED STATES PATENT OFFICE RAZOR, BLADE snARPENEn Edward A. Johnston, Chicago, Ill. 7 Application December. 30, 1935, Serial No. 56,653

Claims..

ing mechanism having a mode of operation designed to impart a type of stroke or movement between the abrasive elements and blade which will act most quickly in producing correct sharpening effects on the cutting edge or edges of a blade. Another purpose is to provide the mechanism in compact form suitable for a portable or pocket type sharpener.

The foregoing, as well as other purposes and advantages-hereinafter referred to, are attained by providing means for causing rapid reciprocating movements between a blade and the abrasive elements in the direction of the width of. the blade. This because it is well established that the most eflicient shaving edge for a razor blade is one having irregular microscopic projections or teeth which constitute the actual cutting edge, all lying substantially parallel and in the plane of the'blade. This condition will result from movement of the abrasive against the sides of the blade edge at substantially'right angles to the line of the cutting edge and crosswise of the blade. It will not result if the movement is circular or orbitahas excessive movement be- 'tween the abrasive and blade lengthwise of the blade edge causes the projections referred to to incline towards each other and even to overlap, therefore giving a poor shaving edge.

In themechanism embodying the present invention the blade sharpening movements are quick and transverse to the longitudinal axis of the blade and substantially rectilinear, such.

I axial movement of the blade as occurs being slow and intermittent and designed to present the blade edges uniformly to the abrasive, all orbital or curvilinear sharpening movements or strokes being eliminated, as will be better understood from the following description and by reference to the accompanying drawing, where, Figure 1 is a top or plan view of the device in the size preferred for manufacture, the course of an actuating cord for same-being shown in broken lines;

Figure 2 is a plan view on an enlarged scale with the cover and end walls of the casing omitted;

Figure 3 is an end view of Figure 2;

Figure 4 is a vertical longitudinal section or! substantially the line 4-4 of Figure 3;

Figure 5 is a vertical longitudinal section on line 5-5 of Figure 3 with the upper portion of the casing broken away;

Figure 6 is a detail view of a bottom bearing plate in the casing as viewed on section line 8-6 5 of Fig. i;

Figure 7 is a detail view of the guiding means and pulleys over which the actuating cord passes; and

Figure 8 is a diagrammatic view illustrating the path of movement followed by any given point on the cutting edges of a blade subjected to the operation of thedevice.

In the particular embodiment of the invention chosen for the purposes of this disclosure, there is provided an oblong box or casing of quadrilateral form comprising a main or body portion ill and a cover H which is preferably hinged as at l2 to one longitudinal side of the casing body. Any suitable catch or latch, as at It, can be provided to hold the cover shut.

In the cover there is fastened, as by clips it (Fig. 4), an abrasive member or head It which preferably consists of an oblong square frame or plate, open at its center, and provided on its opposite longitudinal margins with abrasive elements it each consisting of a series of equally placed plate-like teeth or lugs I! which are higher at their outside edges than at their inside edges and therefore present outer or exposed edges which are inclined towards the longitudinal median line of the abrasive head.

The body of the casing contains a complemental abrasive head it which is a duplicate of the one above described and is positioned to face the opposed abrasive elements on the head It. The lugs or teeth H) on this head are disposed in ofiset relation to the lugs H on head it and the higher portions of the lugs on the respective heads therefore inter-engage or mesh as best shown by Figures 3 and 4 and present inv wardly facing V-shaped grooves. The head It is mounted so as to be yieldably movable and this is effected by providing it with end pins or trunnions which engage in vertical slots it in guide and supporting arms 22, formed as the upturned ends of a supporting plate 23. The head it is supported and pressed upwardly by abowed wire spring M of hairpin shape the middle portion of'which bears on the plate 23 while the opposite ends engage the opposite longitudi naledges of the head I 8. This head may, therefore, rock on spring 24 and may move inwardly as its end pins 20 are guided in the slots 2 I.

The supporting plate 23 rests on spacing blocks 25 in the casing which are mounted on outwardly bent ears 26 provided on the upturned ends or flanges 21 of a base plate 28 secured on the bottom of the casing. Bolts 29 fasten the spacing blocks 25 and plate 23 to the ears 26. Centrally of the base plate 28 there is journaled the lower end of a vertical actuating shaft 30 which has its upper portion journaled in a bearing formed in a projecting portion 3| of the supporting plate 23. This shaft actuates the blade reciprocating mechanism, a preferred form of which is now to be described.

At about its middle the shaft 30 has fixed to it a drive pulley 32 around which is passed an actuating cord 33 which is confined in a tubular guide 34 which extends around pulley 32 and around idler pulleys 35 journaled on pins secured to the under side of supporting plate 23, the tubular guide being open adjacent the pulleys to expose the cord. Above its bearing 3| in plate 23 the shaft 30 extends between the arms of spring 24 to a central point in the opening of the lower abrasive head 18 where it terminates in an eccentrically positioned pin or crank 36 (Figs. 2 and 4). Shaft 30 and pin 38 impart rocking movement to an arched blade carrier 31. This carrier has a straight. flattened, upper bar 38 formed with an elongated slot 39 which receives the eccentric pin 38. The flat upper face of bar 38 has a pair of longitudinally spaced lugs or bosses 40 adapted to loosely engage in the openings of standard wafer type razor blades. The arms of the carrier 31 extend downward and outward in the casing as shown by Fig. 4 and their lower ends, adjacent the bottom of the casing, have secured thereto inwardly extending pivot pins 4|. These pivot pins extend through bearings formed in flanges 21 of base plate 28 and through bearing blocks 42 secured on this plate. The carrier 31 rocks on the axis of these pins 4|. Below pulley 32, shaft 38 serves as the bearing on which a substantially heart-shaped cam 43 and a ratchet wheel 44 revolve. The cam and wheel are connected so that they rotate as a unit and the ends of pins 4| contact the peripheral track on cam 43. On the inner side of each arm of the rocking blade carrier 31 there is mounted a spring pressed ratchet pawl 45. These pawls are arranged in opposed relation to each other and are elongated so that they remain in constant mesh with the teeth on wheel 44 during all movements of the carrier and always drive that wheel in the same direction.

The device operates as follows: The cover II is raised and a double edge blade placed on. the bar 38 over lugs .40. The cover is then closed causing the blade edges to be yieldably gripped between the inter-meshing abrasive lugs l1, 19, on the respective heads, the lower one, l8, of which yields to accommodate the blade and permit its movements during operation of the sharpener. The casing is then held in the user's hand and propelled back and forth on cord 33 which is anchored to a hook or the like at one end and has its other end held in the user's free hand. Thistravel of the casing causes rapid rotations of shaft 30 in alternately reversed directions and correspondingly rapid reciprocations or rocking movements of the blade carrier 31 and the blade carried thereby, thus sweeping the blade edges transversely over the abrasive elements, spreading them apart on opposite sides of the heads alternately against the light pressure of spring 24, the throw of the carrier being preferably gazed to carry the blade edges slightly beyond the outer margins of the abrasive elements at each reciprocation, as indicated on Fig. 2, in order to avoid uneven wear and formation of a terminal shoulder on these elements. As the shaft 38 is rotated first in one direction and then the other, the rocking of carrier 31 will impart successive increments of movement in the same direction to wheel 44 and cam 43 through the pawls 45. At the same time, rotation of cam 43 will push on pivot pins 4|, which abut the cam track, and through them move the carrier 31, step by step, first in one direction and then in the other. The movement-imparted to wheel 44 and cam 43 will be continuous in the same "direction and comparatively very slow and intermittent and it must be noted that as the carrier 31 reaches each limit of its throw the movement of the cam, and therefore the movement of the carrier 31 on its longitudinal axis, is momentarily suspended. Therefore, the action is such that the carrier and blade is displaced just enough in the direction of the length of the blade during each swing of the carrier to bring different surfaces on the abrasive elements, which are stationary, into contact with every portion of the blade edges and assure even abrasive action, the paths of movement being essentially as outlined by Figure 8. The effective action on the blade edges is accordingly confined to movements on lines approximately parallel to the transverse axis of the blade and in its plane, and all generally curvilinear or orbital movements of the blade tending to impair perfect restoration of a cutting edge, are eliminated. It will be noted also that all four sides of the cutting edges of a double edge blade will be swept over the abrasive elements with opposite sides of each edge under equal pressure.

The illustrative embodiment of the invention herein disclosed is capable of various modifications and the scope of the invention is to be judged by the following claims.

What is claimed is:

1. In a razor blade sharpener, the combination of a casing having a base-plate, a head spaced above the base-plate and provided with an elongated abrasive surface, an axially shiftable blade carrier pivoted on the base-plate on an axis parallel to the longitudinal axis of the abrasive surface and having a blade receiving portion located parallel to and adjacent one longitudinal edge of the abrasive surface, means on said blade receiving portion for receiving a blade and retaining it substantially on the level of said abrasive surface with its cutting edge lying in contact therewith, means for maintaining said contact, actuating means for rocking said carrier on its pivot at a high rate of speed, and pawl and ratchet mechanism actuated by said rocking movement and connected to the carrier by means for shifting the carrier axially.

2. The combination of claim 1, the means for shifting the carrier axially comprising a cam actuated by the pawl and ratchet mechanism.

3. In a razor blade sharpener, the combination of a casing having a base-plate, a head spaced above the base-plate and provided with an elongated abrasive surface, an axially shiftable blade carrier pivoted on the base-plate on an axis parallel to the longitudinal axis of the abrasive surface and having a blade receiving portion 10- cated parallel to and adjacent one longitudinal therewithfmeans for maintaining said contact.

an actuating shaft journaled in the casing on an .axis at right angles to the pivot-of the carrier and having a crank portion engaging the carrier for imparting rocking movement thereto; a ratchet wheel journaled on the actuating shaft below its crank portion and having a' cam rotatable therewith and-presenting a peripheral camtrack, a spring pressed pawl on the carrier in engagement with the ratchet wheel, and an abutment on the carrier in engagement with the cam track. g

4. In a razor blade sharpener, the combination of stationary abrasive means, a pivotally mounted blade carrier having means in spaced relation to its pivot for positioning a blade with its cutting edge lying in contact with the abrasive means, actuating means for rocking the carrier on its pivotal mounting in the direction of the width of a blade carried thereby, and means included in the actuating means for shifting the carrier baclr and forth on its pivotal mounting through a predetermined range of movement in a direction at right angles to its direction of rocking movement comprising a rotatable cam and means for imparting consecutive increments of movement to said cam in a constant direction-actuated by the rocking movements of the carrier.

5. In a razor blade sharpener, the combination of stationary abrasive means. a movably mounted blade carrier having means for positioning a blade with its cutting edge lying in contact with the abrasive means, an actuating shaft having a. crankconnection with the carrier for rapidly reciprocating the carrier in the direction direction at right angles to its direction of rapid reciprocation.

EDW A. JOEHQETON. 

